Aftermarket Exhaust in New Mexico
Replacing the exhaust system is legal in New Mexico, but a muffler in good working order is required and cutouts or bypasses are prohibited. There is no statutory 'no louder than stock' rule — the standard is that the exhaust must not produce excessive or unusual noise.
Verified against primary sources · August 2026
What the law says
Replacing the exhaust system is legal in New Mexico, but a muffler in good working order is required and cutouts or bypasses are prohibited. There is no statutory 'no louder than stock' rule — the standard is that the exhaust must not produce excessive or unusual noise. Removing the catalytic converter is prohibited by federal law (Clean Air Act § 203) regardless of state rules. Gasoline vehicles from 1968 onward must keep factory emission-control devices in good working order under state law. Emissions testing applies in Bernalillo County only.
Specific Limits
- Cutouts
- prohibited
- Muffler required
- Yes
- Louder than stock
- not addressed; excessive noise standard applies
- Catalytic converter
- removal prohibited by federal law
Exceptions & Exemptions
Must not exceed noise limits, muffler required, catalytic converter tampering prohibited, no straight pipes or cutouts allowed
Frequently Asked Questions
Are aftermarket exhaust legal in New Mexico?
What are the exact aftermarket exhaust limits in New Mexico?
Are there exceptions for aftermarket exhaust in New Mexico?
Street-legal aftermarket exhaust picks
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